Basically, I conducted an interview and the audio sounds loud when I play it through the top left editing window on Premiere, but when I drag it into the timeline it goes quiet. I go on audio gain and it says the peak amplitude is set to -12 for example. Any explanations what is going on/how I can improve the audio?

I tried compressing the audio, which does make it louder, but it also increases the sound of the background traffic noise and makes it sound strange.